A device of the kind referred to above is applicable to testing long guideways of tool machinery and for determining angular deviations between the axis of parts of large machines. The device here serves as an adjusting collimator having a collimating beam which can be observed in a telescope which is appropriately configured. If the collimating mark imaged at infinity of the adjusting collimator is configured so that it supplements a sighting mark in the telescope in a manner to form a symmetrical figure, then deviations which occur under rough operating conditions can be easily recognized and also measured with appropriate calibration. In this connection and depending upon the type of machine, extreme mechanical and thermal stress conditions can occur with respect to the adjusting collimator.
Up to the present time, adjusting collimators were utilized which were made up of several optical elements. Devices of this kind are accompanied in operation by very substantial difficulties because the correct adjusted condition of the elements with respect to each other is lost under high stress conditions. It is practically not possible to guarantee this adjusted condition without damage occurring to the optical elements in the presence of high mechanical stress.